STAHL CraneSystems Wire Rope Hoists Deployed in Austria Tunneling Project

ACIMEX, at home in the heart of France’s Loire Valley, has offered bespoke solutions in the heavy-duty hoisting sector for 45 years. Frequently incorporating technology from STAHL CraneSystems, the company specializes in systems that help transport large loads using air vacuum technology or hydraulic and mechanical grabs. Working closely together, the engineers of the two companies build machines used around the world in the construction, metallurgy, aviation and energy industries.

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Tunneling requires strong and reliable machinery to ensure safe tube construction. To this end, ACIMEX manufactures segment trolleys and erectors that handle the individual precast elements at the tunnel construction site, including the segment trolley, fitted with a vacuum lifter. Their products are also used to grip and lift the segments from the service train and transport them deeper inside the tunnel. There, they are picked up by segment erectors with the help of an air vacuum and placed in their final position.

How does the technology work? Fitted with two lateral rubber suction cups fastened underneath the chassis and a central vacuum pump, the ACIMEX segment erector can turn the elements up to 360 degrees in the X, Y and Z direction. Parts weighing up to 20 tons are lifted in this way to the highest possible position and placed with a precision of ± 5 degrees. STAHL CraneSystems regularly provides the hoisting technology that performs this work.

In Semmering, Austria, a 27.3-kilometer-long railway tunnel between Gloggnitz in Lower Austria and Mürzzuschlag in Styria was being constructed under the northern Alps. To develop machines for this challenging project, ACIMEX ordered three identically constructed wire rope hoists from STAHL CraneSystems to adjust the precast elements picked up by the segment erectors. Manufactured in STAHL CraneSystems Künzelsau plant, the three SHF 5020-40 wire rope hoists featured 1/1 reeving and a length of two.

For this application, the customer required an above-average lifting speed, which was achieved by using a hoist controller with frequency inverter and motor encoder for closed-loop control. The closed-loop control, combined with software, makes it possible to compare the actual speed of the hoist with the set speed and then adjust it if necessary. This allows for lifting speeds of 7 to 12 meters per minute. The frequency inverter further enables smooth acceleration and deceleration movements during the lifting process.

STAHL CraneSystems delivered the hoists to ACIMEX in April 2017. The successful and timely completion of the machines enabled ACIMEX to meet the project’s needs to ensure the tunnel is constructed on time.